This study is going to make a whole lot of people upset. It’s a large, well designed randomized control trial with a really long follow-up period. The people in the mammogram groups actually complied with screening in surprisingly high numbers. It’s hard to find fault with much of this. The data make a really good case that universal screening with mammograms does almost no good, and likely does harm.

In a major cancer screening development, a study from the British Medical Journal found that an annual screening mammography didn’t result in a mortality benefit . . . Worse, mammograms overdiagnosed cancers, leading to unnecessary mastectomies, radiation therapy and chemotherapy.

What makes this most recent report so compelling is its scope—it’s huge! Almost 90,000 women were followed over 25 years, and were randomly assigned to a treatment group (annual mammogram) and a control group (no mammogram).

That’s as close to the “gold standard” as you can get.

In the annual mammogram group 500 women died of breast cancer; in the control or no mammogram group, 505 women died of breast cancer. Statistically, there was no difference.

Yes, breast cancers were found earlier in the mammogram group, but early detection and treatment did not correlate with a lower death rate. And sometimes mammograms led to over-diagnosis and over-treatment, ultimately causing more harm than good.

Guidelines will keep changing

What now?

In 1980, when I began nursing, there were no breast cancer specialists (general surgeons did all the mastectomies), and no one was screened for breast cancer. Mammograms were only ordered to help diagnose a breast lump.

But in 1980, Susan G. Komen died of breast cancer at the young age of 33. In 1982, her sister founded the Susan G. Komen Breast Cancer Foundation, and breast cancer research and screening exploded.

Since the early-1980s, the Komen foundation has done such a great job spreading the word about breast cancer and breast self exam (BSE) and screening mammograms, that every woman now in her 50s and 60s will have a difficult time accepting anything less than annual mammograms. Physicians, too, have clung to the annual mammogram as the standard of care.

(Oh, and the specialty breast clinics that have sprung up in the last two decades make a LOT of money—I’m sure they don’t want to see fewer mammograms, either.)

As Dr. Pho says, “As we’ve seen with other screening tests, it’s difficult to reduce cancer screening once the proverbial cat’s out of the bag.”

In 2009, the USPSTF issued controversial new recommendations that screening mammograms should only be performed every 2 years between the ages of 50 and 74. Mammograms before age 50 could be done if the patient’s history warranted it, but there was no clear evidence that mammograms after age 75 were of any value.

Needless to say, these new guidelines caused a bit of an uproar in the breast cancer community, with most professional groups, including the American Cancer Society, still recommending women get yearly mammograms beginning at age 40.

Last November, the USPSTF said it was going to review again its recommendations for mammography, and no doubt this latest information from the British Medical Journal will be viewed as significant.

Talk to your insurance company and your doctor

The decision to start regular, biennial screening mammography before the age of 50 years should be an individual one and take patient context into account, including the patient’s values regarding specific benefits and harms. Grade: C recommendation.

The USPSTF concludes that the current evidence is insufficient to assess the additional benefits and harms of screening mammography in women 75 years or older. Grade: I Statement.

The Affordable Care Act mandates that all preventive services receiving an A or B grade from the USPSTF be covered without cost sharing (co-pays or deductibles). Legally, therefore, insurance companies only have to pay for a mammogram every other year for women between the ages of 50 and 74. (Except Medicare, which is required to pay for annual mammograms from age 40 up.)

If you are under 50, over 74, or your doctor recommends yearly mammograms, check with your insurance company to make sure that it will be paid for.

Most private insurance companies are still paying for annual mammograms over the age of 40, but if the USPSTF degrades their recommendation to a D (net harm outweighs net benefit), insurance companies might not need to pay for mammograms at all.

Screening mammography is a big business and it is expensive. Under our current screening strategy (annual mammograms age 40-85), the cost is about $7.8 billion/year.

If insurance companies can find a way to trim those costs, they will.

But, of course, it will probably be several years before any new recommendations are made.

Dr. Pho writes:

You will undoubtedly hear many stories of patients who would rather be 100% informed and risk overdiagnosis than live with the unknown. Peace of mind cannot be quantified, yet still has value for many patients.

My approach? Same as always with cancer screening issues shaded in grey. Make mammograms an individual patient decision. Inform patients of the USPSTF recommendations and the results of the BMJ study, then get a sense of their values and how important it is that they know their breast cancer status.

Then make a shared decision whether to order a mammogram or not, which may be different for each individual patient.